This standing abdominal exercise is a lot more fun than a crunch, and it manages to hit several other major muscle groups at the same time.
It's demonstrated here by fitness instructor John Garey, who uses it at his namesake Long Beach studio and also on his "Core Power & Stamina" DVD.
What it does
The medicine ball extension challenges your shoulders and core, while the leg lift on the opposite side tones your inner and outer thighs.
What to do
Stand with your feet hip-width apart, knees soft, holding the medicine ball with both hands above your head. Slowly lean to your right side, using the ball to help pull you over, as you lift the left leg out to the side.
As you lean into the move, let go with the top hand and bring it straight out to your left side around shoulder height at the same time you bring the ball out to the right side, balanced on your palm. Lean over as far as you can go and still manage to stabilize, while making sure your head is in line with your spine. Pause before returning the ball and your arms to the starting position as you bring your leg down to the floor. Switch sides, extending the ball to the left side as you lift your right leg.
You may find this move is easier on one side than on the other, Garey says. With regular practice, it can help improve that muscular disparity and your overall balance.
Do two sets of 10 to 20 repetitions on each side with a ball of 2 to 8 pounds.